Spirit-level



(No Model.)

, L. L. DAVIS.

SPIRIT LEVEL. No. 297,574. Patented Apr. 29, 1884,

' Z g mma I BY Z ATTORNEY NITED STATES LEONARD L. DAVIS, OF SPRINGFIELD, MASSACHUSETTS.

SPIRIT-LEVEL.

SPECIFICATION forming part of Letters Patent No. 297,574, dated April 29, 1884.

Application filed March 10, 1884. No model.)

To all whom it may concern:

Be it known that I, LEONARD L. DAVIS, a citizen of the United States, residing at Springfield, in the county of Hampden and State of Massachusetts, have invented new and useful Improvements in Spirit-Levels, of which the following is a specification.

This invention relates to improvements in spirit-levels, the object being to provide improved means for hanging the bubble-glass ease therein, whereby it is rigidly held in proper position in the level and is easily adjusted to correct any variations that may arise from any cause between the level line of the glass and the faces of the level.

In the drawings forming part of this specification, Figure 1 is a side elevation of a spirit level having the bubble-glass and its case hung therein according to my invention. Fig. 2 is a transverse section through line as m, Fig. 1. Fig. 3 is a plan view, and Fig. 4adetail view.

In the drawings, A is the level, which is provided with a central longitudinal opening, B, intermediate between its upper and lower faces, in which opening the bubble-glass case a, containing the usual bubble-glass, is hung. The case a is provided with aplug, b, at each end, which enters the case a short distance, as shown. The level A is provided with two screw-holes, e, through each face in a line with each other, and in a vertical central line through the opening B. Each of said screwholes is counterbored to make the diameter larger for a certain distance from the face of the level toward the center, that portion thereof immediately adjoining the opening B being of smaller diameter. The said screw-holes are made of the form described, to adapt them to receive a screw, 0, Fig. 4, which has an elongated cylindrical head and a plain shank of smaller diameter than the head. The larger portion of the screw-hole e and the cylindrical head of screw 0 are correspondingly threaded, the latter being thus adapted to be screwed into the level A, as shown in Fig. 2.

I Thus the plain shanks of the screws 0 from one face ofthe level pass through the smaller portions of their screw-holes into the opening Bin the level directly opposite the ends of the screws, which enter from the opposite side.

The bubble-glass case a and the plugs 72 in the ends thereof are perforated on opposite sides, to receive the ends of the screws 0, as shown in Figs. 1 and 2. The case a is placed in the level and properly adjusted as follows: The screws 0 are turned back far enough to permit of placing the case a between their points, when the screws are turned to cause their points to enter the case and the plugs, as shown. The level is then placed upon a true level surface, and'the screws 0 are turned out and in one after another, to vary the line of the case a relative to the face of the level, until the bubble-glass is found to indicate that the case is in a correct position.

The abovedescribed manner of constructing the case a and hanging it in the level provides very convenient means for replacing a broken glass with a whole one, for it is only necessary to withdraw the screws from one end of the case a, swing its free end outward upon the points of the other two screws, withdrawing the plug I), replace the broken glass with a perfect one, replace the plug, swing the case back between the screws, and adjust as above described.

Vhat I claim as my invention is A spirit-level having a longitudinal opening, B, between its opposite faces, two screws passing through each of said faces, and having their points terminating opposite each other within said opening, and a bubble-glass case adapted to be hung upon the points of said screws, all combined and arranged sub stantially as set forth.

' LEONARD L. DAVIS.

Witnesses:

WM. H. OHAPIN, J. D. GARFIELD. 

